The peninsula is mountainous, with several peaks reaching over 1,000 meters above sea level, the tallest being Kerling (1,538 m).

A few permanent glacial ice caps still exist in central Tröllaskagi, but they are all rather small.

Human settlement is only extant in the relatively flat lowlands along the coast and in the valleys, but these lowlands are densely populated by Icelandic standards with important agricultural regions and a few towns and villages that mostly base their livelihood on fisheries.

Those settlements are (clockwise around the peninsula beginning in Skagafjörður): Hofsós, Hólar, Siglufjörður, Ólafsfjörður, Dalvík, Árskógssandur [ˈaurˌskouksˌsantʏr̥], Hauganes, Hjalteyri, Hrafnagil and the largest being Akureyri.

The Ring Road runs through Tröllaskagi between Skagafjörður and Eyjafjörður through a mountain pass called Öxnadalsheiði [ˈœkstnaˌtalsˌheiːðɪ] where the road reaches a maximum elevation of 540 meters above sea level which can sometimes pose a problem during wintertime.